I'm displaying a Bootstrap alert that automatically fades after some time, by creating a JS module that extends FormView and using the js_class attribute in my view. I've found that when I use FormRenderer.include({...}), the code works as expected, but when I use FormRenderer.extend({...}), the error self.renderer.displayMessageAlert is not a function is raised. I'd prefer to extend over include, so if anyone knows how to make the code work with extend, I'd appreciate it. My code is:

odoo.define('my_module.FormAlertView', function (require) {
  "use strict";

  var FormView = require('web.FormView');
  var FormController = require('web.FormController');
  var FormRenderer = require('web.FormRenderer');

  var viewRegistry = require('web.view_registry');

  var FormAlertController = FormController.extend({
    saveRecord: function () {
      var self = this;
      return this._super.apply(this, arguments).then(function () {
        self.renderer.displayMessageAlert();
      })
    },

  });

  var FormAlertRenderer = FormRenderer.extend({
    displayMessageAlert: function () {
      this.$('.o_alert_fade').addClass('in');
      window.setTimeout(function () {
        $('.o_alert_fade').removeClass('in');
      }, 2000);
    },
  });

  var FormAlertView = FormView.extend({
    config: _.extend({}, FormView.prototype.config, {
      Renderer: FormAlertRenderer,
      Controller: FormAlertController,
    })
  });

  viewRegistry.add('form_alert_view', FormAlertView);

  return FormAlertView;
});